The engine has a nkockig sound..could this be caused by a bad knock sensor?

bad fuel damaged engine bearings rod piston crank cam timing slack timing off cam actuators etc check for trouble codes

Well the knock sensor does not make any noise. It senses the vibration in the engine if there is a spark knock to let the computer know to slow down the spark timing.
You probably have a weak piston or lifter or rod bearing making the noise.

The knock sensor is generally very reliable and the ones I have tested have been capacitive and I tested them with an old LCR bridge.

The knock sensor is essentially a microphone that will detect knocking or detonation caused by bad fuel or overheating or too much ignition advance and the ECU will retard the timing to protect the engine.

A few early electronic management systems were programmed to periodically advance the timing until detonation was heard by the knock sensor when it would retard until the knocking stopped thus maintaining the maximum pressure on the pistons for the fuel input.

The mechanical safety of the engine is placed at risk if it is run with a bad sensor, though a bad sensor should cause the engine brain to use its pre-programmed values to compensate.

I would go with the engine being bad.
A knock sensor only sends a signal to the engine computer when there is a vibration or noise like a spark knock. The computer then adjusts spark timing to compensate.
If the engine is knocking such as a bearing knock, the sensor will be activated.

Meloe77, there's a high possibility you have a mechanical failure inside the engie causing the knocking sound. (Check the oil?)
The reason for shutting off is because the knock sensor can hear it, and the powertrain control module (PCM, herefore) is trying to detune the engine to eliminate the sound, (as if it were caused by bad gasoline.) The fact that there is a mechanical knocking sound, means that the sound cannot be eliminated by detuning of fuel or spark mapping, therefore it starves for fuel and/or spark causing the engine to stop running.
My recommendation: Have the vehicle TOWED to a reputable mechanic and ask him if its possible that I'm right.

The knock sensor tells the computer when to fire the spark plugs. A bad sensor can cause a misfire,ping and lose ignition timing. If you have a bad knock sensor you should replace it ASAP as it can cause damage to the engine.

Probably a sticking valve lifter. Try putting a cup of transmission oil in the engine crank case, or any off the shelf product that is made for said problem. If it doesn't stop, you will have to get it looked at and repaired. It will eventually cause engine failure.
No, it isn't the knock sensor. The knock sensor causes the engine light to come on when there is a problem. It doesn't knock.

I think it not real probable that the cause of your knock sensor code is the result of bad gas. However, I suppose it IS possible. Most knock sensor codes are caused by engine mechanical problems like bad pully bearings, loose timing chains, broken valve springs, collapsed valve lifters, etc. that would cause a "knocking" or "tapping" in the engine.

The next most probable cause would be damaged knock sensor wiring. I have fixed many that have had damage from rodents getting into the engine compartment and chewing on the wires. Depending on which engine your Silverado is equipped with, the knock sensor could be mounted between the cylinder heads in the valley under the intake manifold. Mice like it under there.

Then again, it all depends on WHAT KIND of knock sensor code you are getting. For 2000 Silverado there are 3 possible knock sensor codes: P0325, P0327, P0332. The diagnostics (and possible causes) change depending on which code you have.

P0332 - Knock Sensor 2 Circuit Low Input (Bank 2)

The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the Powertrain Control Module (PCM) or Engine Control Module (ECM).

Causes for P0332 DTC:
- Knock sensor circuit short to GND.
- Knock sensor circuit short to PWR.
- Knock sensor circuit open.
- Damaged knock sensor.
- PCM or ECM failure.

Solutions:
- Repair or resecure the harness or connector.
- Replace the knock sensor.

Your best bet is to just replace the knock sensor for sensor 2 bank 2. Call Auto Zone with part number SU1282 this is the OEM replacement.

The knock sensor looks like this:

check all ground wires to these sensors. Even corrosion will cause codes to pop up